In fuel injection apparatus having an injector delivering fuel to an engine induction passage, the presence of fuel vapor bubbles in the liquid fuel supplied to the injector may adversely affect fuel delivery by the injector. Accordingly, particular care is taken to avoid heating or otherwise handling the fuel in a manner which would generate fuel vapor bubbles.
In addition, in fuel injection apparatus having an electronic drive module for operating an injector, provision must be made to cool at least some of the electronic components within the electronic module to prevent excessive temperatures within the module. In one proposal for cooling an electronic injector drive module, represented by U.S. Pat. No. 3,785,354, heat generated by the module was conducted through an air inlet throttle body, and air flow through the throttle body absorbed and carried the heat into the engine. However, such a method of cooling an electronic injector drive module has not been considered practical in apparatus where fuel supplied to the injector flows through passages formed in the throttle body.